Fuel Cell System and Control Method Thereof

Abstract

The system may comprise a fuel cell stack, a hydrogen supply line configured to be coupled to an anode side of the fuel cell stack and supply hydrogen to the fuel cell stack, a hydrogen supply valve, associated with the hydrogen supply line, configured to adjust an amount of hydrogen supplied to the fuel cell stack, and a controller configured to determine, based on a pressure boost request to boost a hydrogen supply pressure, a front-end hydrogen pressure at a front end of the hydrogen supply valve, determine, based on the determined front-end hydrogen pressure, an opening command value of the hydrogen supply valve, and control, based on the determined opening command value, an opening degree of the hydrogen supply valve to boost the hydrogen supply pressure.

What is claimed is: 
     
         1 . A system comprising:
 a fuel cell stack;   a hydrogen supply line configured to be coupled to an anode side of the fuel cell stack and supply hydrogen to the fuel cell stack;   a hydrogen supply valve, associated with the hydrogen supply line, configured to adjust an amount of hydrogen supplied to the fuel cell stack; and   a controller configured to:
 determine, based on a pressure boost request to boost a hydrogen supply pressure, a front-end hydrogen pressure at a front end of the hydrogen supply valve, 
 determine, based on the determined front-end hydrogen pressure, an opening command value of the hydrogen supply valve, and 
 control, based on the determined opening command value, an opening degree of the hydrogen supply valve to boost the hydrogen supply pressure. 
   
     
     
         2 . The system of  claim 1 , wherein, based on the pressure boost request, the controller is further configured to:
 determine whether a required state or a state of the fuel cell stack satisfies a precondition, and   determine, based on the required state or the state of the fuel cell stack satisfying the precondition, the front-end hydrogen pressure.   
     
     
         3 . The system of  claim 2 , wherein, based on a required pressure boost amount associated with the pressure boost request being greater than or equal to a reference pressure boost amount, the controller is further configured to determine that the required state satisfies the precondition. 
     
     
         4 . The system of  claim 2 , wherein the controller is further configured to:
 determine a hydrogen concentration on the anode side of the fuel cell stack, and   determine, based on the determined hydrogen concentration being less than or equal to a reference concentration, that the state of the fuel cell stack satisfies the precondition.   
     
     
         5 . The system of  claim 1 , wherein the controller is further configured to:
 determine an operating state of the fuel cell stack, and   determine, based on the front-end hydrogen pressure and the determined operating state, the opening command value.   
     
     
         6 . The system of  claim 5 , wherein the controller is configured to:
 derive a maximum duty value of the hydrogen supply valve, wherein the hydrogen supply valve is configured to match the front-end hydrogen pressure and the determined operating state through a prestored data map, and   determine, based on the derived maximum duty value, the opening command value.   
     
     
         7 . The system of  claim 5 , wherein the controller is further configured to:
 determine an oxygen crossover rate on the anode side of the fuel cell stack, and   determine, based on the determined oxygen crossover rate, the opening command value.   
     
     
         8 . The system of  claim 1 , wherein, after controlling the opening degree of the hydrogen supply valve, the controller is further configured to:
 determine an operating state of the fuel cell stack, and   determine, based on the hydrogen supply pressure reaching a boost target pressure while satisfying a pressure boost condition corresponding to the determined operating state, that boosting of the hydrogen supply pressure has been completed.   
     
     
         9 . The system of  claim 8 , wherein, based on the fuel cell stack being in a start-up state, the controller is further configured to determine, based on the hydrogen supply pressure reaching the boost target pressure within a required start-up time, that boosting of the hydrogen supply pressure has been completed. 
     
     
         10 . The system of  claim 8 , wherein, based on the fuel cell stack being in a shutdown state, the controller is further configured to determine, based on the hydrogen supply pressure reaching the boost target pressure within a required shutdown time, that boosting of the hydrogen supply pressure has been completed. 
     
     
         11 . The system of  claim 8 , wherein, based on the fuel cell stack being in an idle state, the controller is further configured to determine, based on the hydrogen supply pressure reaching the boost target pressure while a boosting rate of the hydrogen supply pressure satisfies a target boosting rate, that boosting of the hydrogen supply pressure has been completed. 
     
     
         12 . The system of  claim 8 , wherein, based on the fuel cell stack being in a normal drive state, the controller is further configured to determine, based on the hydrogen supply pressure reaching the boost target pressure within a start response time, that boosting of the hydrogen supply pressure has been completed. 
     
     
         13 . The system of  claim 1 , wherein, after controlling the opening degree of the hydrogen supply valve, the controller is further configured to:
 determine a hydrogen flow rate of supplied hydrogen until boosting of the hydrogen supply pressure has been completed, and   perform, based on the determined hydrogen flow rate exceeding a reference flow rate, a purging process.   
     
     
         14 . A method performed by a fuel cell system for controlling the fuel cell system, the method comprising:
 determining, based on a pressure boost request to boost a hydrogen supply pressure, a front-end hydrogen pressure at a front end of a hydrogen supply valve;   determining, based on the determined front-end hydrogen pressure, an opening command value of the hydrogen supply valve; and   controlling, based on the determined opening command value, an opening degree of the hydrogen supply valve to boost the hydrogen supply pressure.   
     
     
         15 . The method of  claim 14 , wherein determining the front-end hydrogen pressure comprises:
 determining, based on the pressure boost request, whether a required state or a state of a fuel cell stack of the fuel cell system satisfies a precondition; and   determining, based on the required state or the state of the fuel cell stack satisfying the precondition, the front-end hydrogen pressure.   
     
     
         16 . The method of  claim 14 , wherein determining the opening command value comprises:
 determining an operating state of a fuel cell stack of the fuel cell system; and   determining, based on the front-end hydrogen pressure and the determined operating state, the opening command value.   
     
     
         17 . The system of  claim 16 , wherein determining the opening command value comprises:
 deriving a maximum duty value of the hydrogen supply valve, wherein the hydrogen supply valve is configured to match the front-end hydrogen pressure and the determined operating state through a prestored data map, and   determining, based on the derived maximum duty value, the opening command value.   
     
     
         18 . The method of  claim 16 , wherein determining the opening command value comprises:
 determining an oxygen crossover rate on an anode side of a fuel cell stack of the fuel cell system; and   determining, based on the determined oxygen crossover rate, the opening command value.   
     
     
         19 . The method of  claim 14 , further comprising, after controlling the opening degree of the hydrogen supply valve;
 determining an operating state of a fuel cell stack of the fuel cell system; and   determining, based on the hydrogen supply pressure reaching a boost target pressure while satisfying a pressure boost condition corresponding to the determined operating state, that boosting of the hydrogen supply pressure has been completed.   
     
     
         20 . The method of  claim 14 , further comprising, after controlling the opening degree of the hydrogen supply valve:
 determining a hydrogen flow rate of hydrogen supplied until boosting of the hydrogen supply pressure has been completed; and   performing, based on the determined hydrogen flow rate exceeding a reference flow rate, a purging process.